Two Novel Stopping Criteria for Iterative Decoding of Bit-Interleaved Coded Modulation

Abstract

Stopping criterion is an efficient technique to reduce the unnecessary iterations of the iterative decoding process. Up to now, almost all the existing stopping criteria are designed for turbo-decoder, not for bit-interleaved coded modulation with iterative decoding (BICM-ID) receiver. Since the differences between the iterative schemes in turbo-decoder and BICM-ID receiver, these existing stopping criteria need greater computational complexity or extra storage when they are used in BICM-ID. This paper proposes two efficient stopping criteria, called AEV Type-I criterion and AEV Type-II criterion respectively, for BICM-ID receiver. Since both of them are based on average entropy value (AEV) of the decoding results, they have different advantages. Simulation results show that compared with the existing stopping criteria, the AEV Type-I criterion uses the least iteration number and sacrifices very small BER performance at high SNRs; the AEV Type-II criterion takes better trade off between the average iteration numbers and the performance degradation in the whole SNR region. Furthermore, the calculation of AEV is very simple. By using the proposed two AEV criteria, the average iteration number is obviously reduced and the performance degradation is very small.